To actually bridge the gap between business perspective and technical perspective, the prerequisite is to provide a comprehensive process modeling framework for business processes. Different from the previous traditional process methodologies, our work is neither only industrial process graphic-modeling nor pure theoretical studies. We mainly focus on the semantically-enhanced process description model. We propose the semantic modeling framework for business processes, i.e. BPMO: basically, we determine the description requirements for the whole business process lifecycle involving process discovery, composition and execution; furthermore, we refine the comprehensive semantic Web services conceptual model WSMO and make specific extensions to realize the BPMO modeling framework.